1. Field of the Invention
The present invention relates to the construction of chair seats for disabled persons, and more particularly, to a seat design which will prevent problems due to loss of blood circulation in the hip and buttocks area of such persons.
2. Description of the Prior Art
Many disabled persons have no feeling in the lower parts of their bodies due to injuries to the spinal cord or similar problems. Such persons generally utilize wheelchairs during their waking hours to be able to have some mobility. However, a serious problem in many instances results from the lack of blood circulation and air to the lower parts of the body and in particular to the buttocks area. Since the person will sit relatively immobile for many hours, he or she is particularly susceptible to this problem. When this happens the flesh and skin breaks down producing decubiti, commonly referred to as bed sores.
Due to the unfortunate loss of feeling, the person has no immediate indication of the development of such sores which may progress to a serious condition before discovery. The basic problem appears to be restriction of blood circulation due to the torso weight over the hip joint in contact with the seat of the wheelchair or other chair in which the person may spend extensive periods of time. This situation may be aggravated by poor air circulation to the skin. Previous attempts to alleviate this problem include the use of various types of cushions and the like and continuous attention on the part of other persons.
I have found that a special seat for a wheelchair or other invalid chair will prevent this problem. The seat involves a portion which will fold downward just below the buttocks such that the occupant is supported by the thighs and back. While there have been wheelchairs in the past in which the seat may be dropped, such as U.S. Pat. Nos. 3,051,368 and 3,062,582, these mechanisms are for the purpose of permitting the occupant of the wheelchair to have access to a toilet bowl and therefore no support is provided when the seat is displaced. A typical example is U.S. Pat. No. 3,719,390 in which a pivoted seat simply swings completely clear of the seat area of the chair. The occupant must use lifting bars in order to pivot the seat. An articulated seat is taught in U.S. Pat. No. 3,964,786 for the purpose of permitting the occupant to assume any one of three positions, namely sitting, standing or reclining.